[SOLVED] DHCPv6 IPv6 address when using Static IPv4 address on LAN interface

Hello. I have a somewhat unique topology and have stumbled upon a configuration dilemma.

I have two routers in my network, one is running stock firmware and is the gateway to the internet, it has the DHCP server disabled. The other one is running OpenWRT and does not do any routing - it is an access point connected via cable to the main router which also gives some services to the network, mainly DHCP and DNS for IPv4 with static leases. It has a static IP address on the 'lan' interface and uses the stock router as its gateway:
image

Recently my ISP has enabled IPv6 for my connection, using DHCPv6 and Prefix Delegation. On my main router the connection looks like this:

  • There were some images here but as I am a new user, I can only post one image. it looked like this:
  • Internet connection: IPv6 enable
  • IPv6 Addressing Type: DHCPv6
  • LANconnection: IPv6 Enabeld
  • Address Type: RADVD
  • RDNSS disabled
  • ULA Prefix disabled
  • Site Prefix Type: Delegated

(I'm not 100% sure it's correctly configured, but hey, it works!)

All my network devices now receive an IPv6 address from the main router and online IPv6 tests work fine. However, I don't know how to get OpenWRT to request an IPv6 address while keeping its static IPv4 address.

There is also the Global "IPv6 ULA prefix" which is configured, I don't know it can coexist with ISP-provided IPv6 address.

P.S.: A user on the #OpenWRT IRC channel suggested DHCPv6 client as a protocol in System -> Interfaces -> LAN -> Protocol
Is that what I am looking for? Dynamic IPv6 with static IPv4?

Thank you

Add another interface, for example named lan6, using @lan (an alias) as physical interface and configure it as a DHCPv6 client. It will support both DHCPv6 and SLAAC via Router Advertisement. I guess you need the latter since it says "Address Type: RADVD" above under LANconnection.

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Thank you for the reply. Another IRC user suggested I look under the IPv6 anchor in the DumbAP documentation page and suggested the same thing.

I tried doing it through LuCI but could not find @lan or br-lan physical interface (same as 'lan' interface) and did not think to use the "custom interface" option, so I went to the command line and edited /etc/config/network myself to change option iface to @lan

After doing that I have received an IPv6 address and could ping external IPv6 hostnames from command line (so DNS seems to also be working). The last question that I have is why can I see the address in the lan6 interface of the Network > Interfaces page, but not in the overview?
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